Results of TACTICS probably will not lead to incorporation of sorafenib in clinical practice at this time, he concluded. “This will take a while. There is lots of noise in the chemoembolization trials, there are lots of discussions about what should be done.” In addition, “this should be studied in the West and in a large sample size.”
In the CELESTIAL trial, it would have been helpful to see biomarker data (given that tumor MET status may influence benefit from cabozantinib) and patient stratification according to reason for stopping prior sorafenib (intolerance versus progression), according to Dr. Bruix.
Furthermore, pattern of progression was not reported. “What drives a poorer outcome [in HCC] is the extrahepatic dissemination, meaning vascular invasion or extrahepatic spread. The trials, at least as a post hoc analysis, should have nowadays this kind of analysis that I think is not going to be available in the cabozantinib trial,” he said.
The fact that time to progression with cabozantinib was longer than time on the drug hints at possible safety and tolerability issues, according to Dr. Bruix. “This makes me suspect that some patients had something prior to progression that primed treatment interruption. This is something that I would like to see better explored … to understand to what extent the drug is safe, can be managed, or whether there are too many treatment interruptions that can lead to this discrepancy.”